For medical face masks, we often see these characters such as PFE, BFE and VFE. What is the meaning of these indicators? There is a certain correlation between PFE and BFE. For medical face masks, with NaCl aerosol, flow rate 30L/min, when the PFE is higher than 90.0%, the BFE can be higher than 99.0%. Compared with VFE, PFE, when the PFE reach 91.83%, the VFE can reach more than 98%, even higher than 99%. Test aerosol of BFE and VFE are bacteria and bacteriophage respectively, and biological experiment is a very troublesome and complicated process. For mask manufacturers, these indicators are too complex as routine tests. Therefore, some indirect experiences are often used in practice.

ISO 29463 originates from EN1822, which defines EPA, HEPA and ULPA filters commonly used in industry. While ISO 29463 maintains the classification of EPA, HEPA and ULPA.But replace E10-E12, H13-H14 and U15-U17 with the following 13 filter levels. The ISO 29463 can't replace EN 1822, EN 1822 will continue to be valid.

The air conditioning box in the clean workshop of Factory C is manufactured by a new air conditioning factory. It is said that the designer of the air conditioning box is an air conditioning expert from Southeast Asia. The factory began to operate in early autumn. Soon, the weather became cool and t

There is a ring of sealing gasket with good elasticity on the frame of HEPA filter, which closely fits with the high-efficiency air supply outlet. In the process of use, some maintenance and construction personnel will stand on the air outlet. If they are not careful, or the structural strength of t

A clean workshop producing color displays has not been built for long. The air supply volume of the air conditioner has become smaller, and the temperature and humidity are out of control. The temperature is far higher than the set value of 22 ± 1 ℃, reaching 30 ℃, and increases with the increase of